System controller for integrated lighting control panels

An electrical distribution system is provided for selectively connecting an electrical power source to load devices comprising a plurality of panelboards each having a plurality of load circuit positions. A plurality of pairs of circuit breakers and switching devices are each mounted in one of the load circuit positions. Each pair is electrically connected between an electrical power source and a load device for selectively delivering electrical power to load devices. An I/O controller is mounted in the panelboard for controlling operation of the switching devices. The I/O controller includes a communication circuit. A system controller is connected to each I/O controller communication circuit and comprises a programmed controller for commanding operation of the I/O controllers.